This thesis involves studies of different molecular imaging modalities in various stages of prostate cancer (PCa).

Study I investigated the association between uptake of uPAR-PET ligand 68Ga-NOTA-AE105 and Gleason score in 52 PCa patients. A significant correlation between uptake of uPAR ligand and Gleason score was found. These results suggest that uPAR PET/MRI can serve as noninvasive evaluation of PCa.

Study II included 17 patients with advanced PCa treated with Radium-223. The aim was to investigate uPAR PET/CT for early response assessment during Radium-223 therapy. A significant association between tumor uptake of uPAR ligand and survival was found. Furthermore, patients with high uPAR activity had an increased risk of skeletal complications. 

In Study III another method for prognostication and response assessment in Radium-223 therapy was investigated: quantitative assessment of skeletal tumor burden based on bone scintigraphy (Bone scan index). A retrospective study of 88 patients treated with Radium-223 found bone scan index at baseline predictive for overall survival and risk of bone marrow suppression. 

Conclusively, the results indicate that uPAR PET/MRI is a promising method for assessment of localized PCa. In patients treated with Radium-223 uPAR PET/CT yields prognostic value but is less suitable for response assessment. In the same setting bone scan index can provide prognostic information regarding survival and risk of bone marrow suppression.